Explanation:
A: X=4
Step 1: Distribute the 7 within the parenthesis which will give you:
7x - 21 = 7
Step 2: Add over the -21 to the other side of the = which will give you:
7x = 28
Step 3: Divide by 7 on both sides to get the final answer, X=4
B: M=9
Step 1: Multiply by 4 on both sides, to cancel it out on the right, which will give you:
32 = 3m + 5
Step 2: Subtract the 5 from each side, giving you:
27 = 3m
Step 3: Divide by 3 on both sides to get the final answer, M=9
C: X=28
Step 1: Subtract 9 from both sides, giving you:
x/2 = 14
Step 2: Multiply by 2 on both sides to give you:
x = 28 (This will be our final answer, there is nothing left to simplify.)
D: X=3
Step 1: Distribute the 2 on the left and the (-) on the right to give you:
5 + 2x + 10 = 10 - 4 + 5x
Step 2: Combine like terms and simplify to give you:
15 + 2x = 6 + 5x
Step 3: Subtract over the (2x) to give you:
15 = 6 + 3x
Step 4: Subtract over the 6 to give you:
9 = 3x
Step 5: Divide by 3 on both sides to get the final answer, X=3